Survival of European patients with central nervous system tumors

Relative survival after meningioma surgery. A French nationwide population-based cohort study

BACKGROUND

Survival after meningioma surgery is often reported with inadequate allowance for competing causes of death.

METHODS

We processed the Système National des Données de Santé, the French administrative medical database to retrieve appropriate patients' case of surgically treated meningiomas. The Pohar Perme relative survival (RS) method was implement.

RESULTS

A total of 28,778 patients were identified between 2007 and 2017 of which 75% were female. Median age at surgery 59 years. Cranial convexity was the most common (24.7%) location and, benign meningioma represented 91.5% of all meningioma. Median follow-up was 3.5 years interquartile range [3.4-3.5]. At data collection, 2,232 patients were dead. The five-year survival relative to the expected survival of an age- and gender-matched French standard population was 96.2% 95% confidence interval (CI)[95.7-96.8]. Meningioma absolute excess risk of death was 973/100,000 person-years 95%CI[887-1068] (p< .001). The related standardised mortality ratio was 1.8 95%CI[1.7-1.9] (p< .001). In the adjusted model, male gender (hazard ratio [HR] =1.39, 95%CI[1.27-1.54], p< .001), age at surgery (HR=0.97, 95%CI[0.97-0.97], p < .001), type 2 neurofibromatosis (HR=2.95, 95%CI[1.95-4.46], p < .001), comorbidities HR=1.39, 95%CI[1.36-1.42], p < .001), location (HR=0.8, 95%CI[0.67-0.95], p= .0111), pre-operative embolization, (HR=1.3, 95%CI[1.08-1.56], p= .00507), cerebro-spinal fluid shunt, (HR=2.48, 95%CI[2.04-3.01], p < .001), atypical (HR=1.3, 95%CI [1.09-1.54], p= .00307) or malignant histology (HR=1.86, 95%CI[1.56-2.22], p< .001), redo surgery (HR=1.19, 95%CI[1.04-1.36], p= .0122) and radiotherapy (HR=1.43, 95%CI[1.26-1.62], p < .001) were established as independent predictors of RS.

CONCLUSION

This unique study highlights the excess mortality associated with meningioma disease. Many factors such as gender, age, location, histopathological grading, redo surgery influence the RS.

Ibrahimi A, Abu Laban D, Maraqa B, Al-Ani A, Al Sharie S, Al-Hussaini M. Clinical and Molecular Characteristics and Outcome of Adult Medulloblastoma at a Tertiary Cancer Center

Background/Objectives: Adult medulloblastoma is a rare entity, with management data extrapolated from pediatric medulloblastoma cases. We aim to report the clinical characteristics, prognostic factors, and treatment outcome of a cohort of adult patients with medulloblastoma. Methods: Fifty-three patients aged ≥ 18 years with medulloblastoma treated at King Hussein Cancer Center between 2007 and 2019 were retrospectively reviewed. Patients' diseases were staged according to modified Chang's staging system. All patients received adjuvant craniospinal irradiation followed by a posterior fossa boost. Baseline disease characteristics, including molecular subgrouping, were tested as prognostic factors of progression-free survival (PFS) and overall survival (OS) by using univariate analysis. Results: Median follow-up was 70 months (range 37.5-104.5 months). Twenty-two tumors were of the SHH-activated subtype. Conversely, WNT-activated and group 4 tumors had three cases each. Only 37.7% of patients died. The mean 3-year, 5-year, and 10-year OS were 85% (75-95%), 74% (62-87%), and 50% (33-75%), respectively. Significant differences in OS were associated with the extent of surgery (p = 0.017), M stage (p = 0.009), and risk status (p < 0.001). Relapses were detected in 28.3% of cases. The 3-year, 5-year, and 10-year PFS were 81% (71-92%), 75% (63-88%), and 66% (52-83%), respectively. Significant differences in PFS were associated with the extent of surgery (p = 0.008) and risk status (p = 0.012). Molecular subgrouping did not correlate with OS or PFS. Conclusions: Our results revealed poor survival of patients with high-risk disease, which may necessitate the intensification of chemotherapy. Molecular subgrouping did not correlate with the outcome in this cohort.

Glioma Stem Cells-Features for New Therapy Design

On a molecular level, glioma is very diverse and presents a whole spectrum of specific genetic and epigenetic alterations. The tumors are unfortunately resistant to available therapies and the survival rate is low. The explanation of significant intra- and inter-tumor heterogeneity and the infiltrative capability of gliomas, as well as its resistance to therapy, recurrence and aggressive behavior, lies in a small subset of tumor-initiating cells that behave like stem cells and are known as glioma cancer stem cells (GCSCs). They are responsible for tumor plasticity and are influenced by genetic drivers. Additionally, GCSCs also display greater migratory abilities. A great effort is under way in order to find ways to eliminate or neutralize GCSCs. Many different treatment strategies are currently being explored, including modulation of the tumor microenvironment, posttranscriptional regulation, epigenetic modulation and immunotherapy.

CPLX2 is a novel tumor suppressor and improves the prognosis in glioma

BACKGROUND

Glioma is a type of malignant cancer that affect the central nervous system. New predictive biomarkers have been investigated in recent years, but the clinical prognosis for glioma remains poor. The function of CPLX2 in glioma and the probable molecular mechanism of tumor suppression were the focus of this investigation.

METHODS

The glioma transcriptome profile was downloaded from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases for analysis of CPLX2 expression in glioma. RT-qPCR was performed to detect the expression of CPLX2 in 68 glioma subjects who have been followed up. Kaplan-Meier survival analyses were conducted to assess the effect of CPLX2 on the prognosis of glioma patients. The knockdown and overexpressed cell lines of CPLX2 were constructed to investigate the impact of CPLX2 on glioma. The cell growth, colony formation, and tumor formation in xenograft were performed.

RESULTS

The expression of CPLX2 was downregulated in glioma and was negatively correlated with the grade of glioma. The higher expression of CPLX2 predicted a longer survival, as indicated by the analysis of Kaplan-Meier survival curves. Overexpressed CPLX2 impaired tumorigenesis in glioma progression both in vivo and in vitro. Knocking down CPLX2 promoted the proliferation of glioma cells. The analysis of GSEA and co-expression analysis revealed that CPLX2 may affect the malignancy of glioma by regulating the hypoxia and inflammation pathways.

CONCLUSIONS

Our data indicated that CPLX2 functions as a tumor suppressor and could be used as a potential prognostic marker in glioma.

TRIM6: An Upregulated Biomarker with Prognostic Significance and Immune Correlations in Gliomas

This study investigates the expression and prognostic value of TRIM6 in gliomas, the most prevalent primary brain and spinal cord tumors. Our results show that TRIM6 is predominantly overexpressed in glioma tissues and is associated with reduced overall survival, disease-specific survival, and progression-free interval. Furthermore, TRIM6 expression is correlated with WHO grade and primary treatment outcomes. Functional analysis indicates that interactions between cytokines and their receptors play a critical role in the prognosis of glioma patients. A protein-protein interaction network reveals 10 hub genes closely linked to cytokine-cytokine receptor interaction. In vitro experiments demonstrate that silencing TRIM6 impairs the proliferation, invasion, and migration of glioma cells, while overexpressing TRIM6 enhances these abilities. Additionally, TRIM6 expression is positively associated with the abundance of innate immune cells and negatively associated with the abundance of adaptive immune cells. In summary, TRIM6 is significantly upregulated in gliomas and linked to poor prognosis, making it a potential diagnostic and prognostic biomarker. TRIM6 plays a crucial role in promoting cell viability, clonogenic potential, migration, and invasion in glioma cells. It may regulate glioma progression by modulating cytokine-cytokine receptor interaction, leading to an inflammatory response and an imbalance in immunomodulation, thereby representing a potential therapeutic target.

The Current State of Adult Glial Tumor Patients’ Care in Kazakhstan: Challenges in Diagnosis and Patterns in Survival Outcomes

Background: The study aimed to analyze the 5-year survival of adult patients with glial tumors and to define characteristics that are associated with the disease outcomes in Kazakhstan. Methods: Medical records of patients that were surgically treated at the National Center for Neurosurgery during the 5-year period from 2016 to 2020 were collected retrospectively. Patients with a histologically confirmed diagnosis of diffuse astrocytic or oligodendroglial tumor type were included and their survival was assessed with life tables, Kaplan–Meier plot, and Cox regression using STATA 16 statistical software. Results: Almost half of the patients had glioblastoma. The 5-year survival rate of the whole sample was 45.93%. Among Grade 4 patients, 15.6% survived the 5-year mark. Differences in survival between grades 1–3 were not significant. Grade 1 patients demonstrated worse survival rates compared to Grade 2 patients (69% vs. 74%). Worse survival rates were observed among patients of Russian ethnicity and in rural residents. Conclusions: The study described the unusual patterns in survival rates of glial tumor patients in Kazakhstan, pointing to the need for reassessment of diagnostic accuracy and resulting treatment of glial patients in Kazakhstan, and the need to introduce molecular and genetic parameters in tumor type classification. Moreover, the observed difference in survival of different ethnic groups and residents of rural and urban areas should be further investigated and addressed by healthcare professionals.

The Epidemiology of Brain and Spinal Cord Tumors

CNS tumors are a diverse group of neoplasms that emerge from a variety of different CNS cell types. These tumors may be benign, malignant, or borderline in nature. The majority of high grade glial tumors are fatal, with the exception of pilocytic astrocytoma. Primary malignant CNS tumors occur at a global annual rate of 2.1 to 5.8 per 100,000 persons. Males are more likely to develop malignant brain tumors than females, whereas benign meningiomas are more common in adult females. Additionally, gender inequalities in non-malignant tumors peak between the ages of 25 and 29 years. Only a small number of genetic variants have been associated with survival and prognosis. Notably, central nervous system (CNS) tumors exhibit significant age, gender, and race variation. Race is another factor that affects the incidence of brain and spinal cord tumors. Different races exhibit variation in terms of the prevalence of brain and CNS malignancies. This chapter discusses ongoing research on brain and spinal cord tumor epidemiology, as well as the associated risks and accompanied disorders.

Most recent update of preclinical and clinical data on radioresistance and radiosensitivity of high-grade gliomas-a radiation oncologist's perspective

PURPOSE

This review article discusses the studies concerning advances in radiotherapy of high-grade gliomas published in the second half of 2021.

METHODS

A literature search was performed in PubMed using the terms ("gliom* and radio*") and time limits 1 July 2021-31 December 2021. The articles were then manually selected for relevance to the analyzed topics.

RESULTS

Considerable progress has been made in the preclinical field on the mechanisms of radioresistance and radiosensitization of high-grade gliomas (HGG). However, fewer early-phase (I/II) clinical trials have been performed and, of the latter, even fewer have produced results that justify moving to phase III. In the 6‑month period under consideration, no studies were published that would lead to a change in clinical practice and the overall survival (OS) of patients remained similar to that of 2005, the year in which it increased significantly for the last time thanks to introduction of the alkylating agent temozolomide.

CONCLUSION

After 17 years of stalemate in improving the OS of patients with HGG, an in-depth analysis of the causes should be carried out in order to identify whether the research efforts conducted so far, including in the radiotherapeutic field, have been the most effective or require improvement. In our opinion, in addition to the therapeutic difficulties related to the biology of HGG tumors (e.g., high infiltrating capacity, multiple resistance mechanisms, blood-brain barrier), some public research policy choices may also play a role, especially in consideration of the limited interest of the pharmaceutical industry in the field of rare cancers.

KLHDC8A Expression in Association with Macrophage Infiltration and Oxidative Stress Predicts Unfavorable Prognosis for Glioma

Background

The tumor immune microenvironment (TME) is associated with cancer progression and immune escape. Although KLHDC8A has been reported in glioma in vitro, the expression and clinical significance of this gene in clinical samples are unknown.

Methods

The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases were used to evaluate the mRNA expression level of KLHDC8A and its significance in the glioma TME. Tissue microarray-based multiple immunohistochemical staining was conducted to determine KLHDC8A protein levels and characterize the immune signature of tumor-infiltrating immune cells in gliomas.

Results

Tumor cells and tumor-associated macrophages expressed KLHDC8A. The expression of KLHDC8A was higher in glioma tissues than in normal brain tissues and was associated with patient clinical characteristics. Gliomas exhibited a high abundance of macrophages, neutrophils, regulatory T cells, and the immune checkpoint PD-L1, as well as high KLHDC8A expression. Cox regression analysis showed that KLHDC8A+CD68+ macrophages and KLHDC8A predicted unfavorable survival in patients with glioma. Finally, protein-protein interaction network analysis showed that the KLHDC8A expression was associated with hypoxia and oxidative stress.

Conclusions

KLHDC8A is a potential marker for the clinical diagnosis of glioma. The immune characteristics of macrophages play a crucial role in predicting patients with glioma, providing a new avenue for targeted glioma therapy.

Epidemiology of Primary Brain Tumors in the Province of Catania during the 2003-2016 Period

INTRODUCTION

Primary brain tumors (PBTs) account for approximately 2% of all cancers and are associated with significant morbidity and mortality. However, only few epidemiological studies focus on PBTs in Italy. The aim of this study was to evaluate incidence, temporal trend, and survival rate of all PBTs in the province of Catania during the study period.

METHODS

All patients diagnosed with PBTs in the province of Catania during the 2003-2016 were identified through the local cancer registry. All cases were classified by histology according to 2007 WHO classification of central nervous system tumors, using the International Classification of Diseases for Oncology, 3rd edition codes. The incidence rate (IR) was calculated for all PBTs and by gender, histology, age-groups, and behavior. Trend analysis was performed using a piecewise log-linear model.

RESULTS

A total of 3,819 cases were identified with a female/male ratio of 1.45. The IR for all PBTs was 25.3/100,000 person-years (95% confidence interval 24.5-26.1). Most PBTs were nonmalignant (59.5%, IR = 15.0) with a female predominance. Conversely, malignant tumors (32.4%, IR = 8.2) were more common among men, with a female/male ratio of 0.9. The most frequently reported histology was meningioma (39.0%, IR = 9.8), followed by glioblastoma (11.6%, IR = 2.9). A peak of incidence was found in the 75-84 years age-group, with an IR of 77.6/100,000 person-years. Overall, no increase in incidence was observed along the study period.

CONCLUSIONS

The IR of PBTs in the province of Catania is close to incidence reported worldwide. Further studies on risk factors are necessary.

Prognostic and Predictive Biomarkers in Gliomas

Gliomas are the most common central nervous system tumors. New technologies, including genetic research and advanced statistical methods, revolutionize the therapeutic approach to the patient and reveal new points of treatment options. Moreover, the 2021 World Health Organization Classification of Tumors of the Central Nervous System has fundamentally changed the classification of gliomas and incorporated many molecular biomarkers. Given the rapid progress in neuro-oncology, here we compile the latest research on prognostic and predictive biomarkers in gliomas. In adult patients, IDH mutations are positive prognostic markers and have the greatest prognostic significance. However, CDKN2A deletion, in IDH-mutant astrocytomas, is a marker of the highest malignancy grade. Moreover, the presence of TERT promoter mutations, EGFR alterations, or a combination of chromosome 7 gain and 10 loss upgrade IDH-wildtype astrocytoma to glioblastoma. In pediatric patients, H3F3A alterations are the most important markers which predict the worse outcome. MGMT promoter methylation has the greatest clinical significance in predicting responses to temozolomide (TMZ). Conversely, mismatch repair defects cause hypermutation phenotype predicting poor response to TMZ. Finally, we discussed liquid biopsies, which are promising diagnostic, prognostic, and predictive techniques, but further work is needed to implement these novel technologies in clinical practice.

Systemic administration of mesenchymal stem cells loaded with a novel oncolytic adenovirus carrying IL-24/endostatin enhances glioma therapy

Oncolytic adenovirus-mediated gene therapy shows promise for cancer treatment; however, the systemic delivery of oncolytic adenovirus to tumors remains challenging. Recently, mesenchymal stem cells (MSCs) have emerged as potential vehicles for improving delivery. Yet, because the oncolytic adenovirus replicates in MSCs, balancing MSC viability with viral load is key to achieving optimal therapeutic effect. We thus developed an all-in-one Tet-on system that can regulate replication of oncolytic adenovirus. Then, we loaded the novel oncolytic adenovirus carrying interleukin (IL)-24 and/or Endostatin in human umbilical cord blood-mesenchymal stem cells (hUCB-MSCs) for glioma therapy. In vitro assays demonstrated that this novel oncolytic adenovirus could efficiently replicate and kill glioma cells while sparing normal cells. Moreover, doxycycline effectively regulated oncolytic adenovirus replication in the hUCB-MSCs. The doxycycline induction group with dual expression of IL-24 and Endostatin exhibited significantly greater antitumor effects than other groups in a xenograft model of glioma. Thus, this strategy for systemic delivery of oncolytic adenovirus with its oncolytic activity controlled by a Tet-on system is a promising method for achieving antitumor efficacy in glioma, especially for metastatic tumors.

Clinical outcome assessments of motor status in patients undergoing brain tumor surgery

INTRODUCTION

Clinical outcome assessment (COA) is an important instrument for testing the effectiveness of treatments and for supporting healthcare professionals on decision-making. This review aims to assess the use of COAs, and the evaluation time points of motor status in patients with brain tumor (BT) undergoing surgery.

METHODS

We performed a scoping review through MEDLINE, EMBASE, and LILACS databases, looking for original studies in primary or secondary BT, having motor function status as the primary outcome.

EXCLUSION CRITERIA

mixed sample, BT recurrence, and an unspecific description of motor deficits evaluation.

RESULTS

Nine studies met the eligibility criteria. There were 449 patients assessed. A total of 18 scales evaluated these BT patients, 12 performance outcomes measures (PerfO) tested motor function. Four scales were the clinician-reported outcome measures (ClinRO) found in this review, two assessed performance status, and two rated ambulation. Two patient-reported outcome measures (PRO) appraised functionality.

CONCLUSIONS

A variety of instruments were used to assess BT patients. Rehabilitation studies are more likely to associate the use of PerfO and PRO concerning motor and functional status. The use of specific validated scales to the BT population was rare. The lack of a standardized approach hampers the quality of BT patient's assessment.

Satellitosis, a Crosstalk between Neurons, Vascular Structures and Neoplastic Cells in Brain Tumours; Early Manifestation of Invasive Behaviour

The secondary structures of Scherer commonly known as perineuronal and perivascular satellitosis have been identified as a histopathological hallmark of diffuse, invasive, high-grade gliomas. They are recognised as perineuronal satellitosis when clusters of neoplastic glial cells surround neurons cell bodies and perivascular satellitosis when such tumour cells surround blood vessels infiltrating Virchow-Robin spaces. In this review, we provide an overview of emerging knowledge regarding how interactions between neurons and glioma cells can modulate tumour evolution and how neurons play a key role in glioma growth and progression, as well as the role of perivascular satellitosis into mechanisms of glioma cells spread. At the same time, we review the current knowledge about the role of perineuronal satellitosis and perivascular satellitosis within the tumour microenvironment (TME), in order to highlight critical knowledge gaps in research space.

Astrocytoma: A Hormone-Sensitive Tumor?

Astrocytomas and, in particular, their most severe form, glioblastoma, are the most aggressive primary brain tumors and those with the poorest vital prognosis. Standard treatment only slightly improves patient survival. Therefore, new therapies are needed. Very few risk factors have been clearly identified but many epidemiological studies have reported a higher incidence in men than women with a sex ratio of 1:4. Based on these observations, it has been proposed that the neurosteroids and especially the estrogens found in higher concentrations in women's brains could, in part, explain this difference. Estrogens can bind to nuclear or membrane receptors and potentially stimulate many different interconnected signaling pathways. The study of these receptors is even more complex since many isoforms are produced from each estrogen receptor encoding gene through alternative promoter usage or splicing, with each of them potentially having a specific role in the cell. The purpose of this review is to discuss recent data supporting the involvement of steroids during gliomagenesis and to focus on the potential neuroprotective role as well as the mechanisms of action of estrogens in gliomas.

A Nationwide, Population-Based Epidemiology Study of Primary Central Nervous System Tumors in Korea, 2007-2016: A Comparison with United States Data

PURPOSE

The purpose of this study was to determine the epidemiologic characteristics and survival of patients with primary brain and other central nervous system (CNS) tumors in Korea and to compare our findings with those from the United States.

Materials and Methods

We collected data on primary brain and CNS tumors diagnosed between 2007 and 2016 from the Korea Central Cancer Registry. The age-standardized incidence rates (ASRs) and 5-year relative survival rates (RSRs) were evaluated. We applied the classification and definitions of the Central Brain Tumor Registry of the United States to our analysis for direct comparison with United States data.

RESULTS

A total of 115,050 primary brain and CNS tumors were identified, and the ASR of all tumors was 22.01 per 100,000 individuals, which was lower than the 23.41 in the United States. However, the ASR of malignant tumors was significantly lower herein (4.27) than in the United States (7.08). Meningeal tumors were the most common histologic group among all tumors (ASR, 8.32). The 5-year RSR of all primary brain and other CNS tumors was 86.4%, and that of all malignant tumors was 44.1%, which was higher than the 35.8% observed in the United States. Among malignant tumors, glioblastomas had the lowest 5-year RSR (12.1%).

CONCLUSION

In Korea, malignant brain and other CNS tumors have a lower incidence and better survival outcome.

Impact of surgical treatment on the performance status of patients with high-grade gliomas

OBJECTIVES

The objective of our study is to evaluate the impact of neurosurgical operative treatment on the performance status assessed by the Karnofsky Performance Scale (KPS) in patients with HGG for the first, for the second intervention and for the different age groups.

METHODS

A group of 425 patients operated consecutively for high-grade gliomas were included in this study. The performance status was evaluated preoperatively and 15 days postoperatively with the KPS. Analyses for the different histological grade, tumor locations and age groups divided by decades have been made.

RESULTS

The initial, preoperative KPS score for patients with grade III tumor was 77.65 and for grade IV - 71.35. Following the first operation mean KPS has a statistically significant increase and reaches 82.24 and 78.41, respectively. The improvement of the performance status after the first operation was significant for all relevant age groups, including the sixth, seventh and eighth decades. Although the obtained mean KPS scores after the second operation did not show improvement there was also no clear evidence for worsening in this group of patients (n = 100) and the negative results obtained were not statistically significant.

CONCLUSION

According to our study, the first operation has a beneficial effect on the performance status in patients with HGG. The results for the second operation are more ambiguous, but there is no clear evidence for worsening of the KPS score after the second intervention. These results were relevant for all age groups, so we may expect amelioration in the performance status even in older patients.

Alkaloids of fascaplysin are promising chemotherapeutic agents for the treatment of glioblastoma: Review

Glioblastoma is one of the most aggressive human brain tumors. Even following all the modern protocols of complex treatment, the median patient survival typically does not exceed 15 months. This review analyzes the main reasons for glioblastoma resistance to therapy, as well as attempts at categorizing the main approaches to increasing chemotherapy efficiency. Special emphasis is placed on the specific group of compounds, known as marine alkaloids and their synthetic derivatives exerting a general antitumor effect on glioblastoma cells. The unique mechanisms of marine alkaloid influence on the tumor cells prompt considering them as a promising basis for creating new chemotherapeutic agents for glioblastoma treatment.

LINC00680 and TTN-AS1 Stabilized by EIF4A3 Promoted Malignant Biological Behaviors of Glioblastoma Cells

Glioblastomas are the most common and malignant intracranial tumors with a low survival rate. Dysregulation of long non-coding RNAs and RNA-binding protein causes various diseases, including cancers. However, the function of LINC00680 and TTN-AS1 in the progression of glioblastomas is still elusive. In this study, we detected that LINC00680 and TTN-AS1 were upregulated in glioblastoma cells. RNA-binding protein EIF4A3 could prolong the half-life of LINC00680 and TTN-AS1. Knockdown of EIF4A3, LINC00680, and TTN-AS1 impaired proliferation, migration, and invasion and inhibited the growth of tumor in vivo and promoted apoptosis of glioblastoma cells. miR-320b was proven to be a target of LINC00680 and TTN-AS1. They interacted with miR-320b as competing endogenous RNAs, which resulted in the reduction of binding between transcriptional factor EGR3 (early growth response 3) mRNA and miR-320b. The accumulation of EGR3 promoted expression of plakophilin (PKP)2, which could activate the epidermal growth factor receptor (EFGR) pathway, leading to the malignant biological behaviors of glioblastoma cells. In summary, LINC00680 and TTN-AS1 promoted glioblastoma cell malignant biological behaviors via the miR-320b/EGR3/PKP2 axis by being stabilized by EIF4A3, which may provide a novel strategy for glioblastoma therapy.

Development of a Microfluidic Culture Paradigm for Ex Vivo Maintenance of Human Glioblastoma Tissue: A New Glioblastoma Model?

BACKGROUND: One way to overcome the genetic and molecular variations within glioblastoma is to treat each tumour on an individual basis. To facilitate this, we have developed a microfluidic culture paradigm that maintains human glioblastoma tissue ex vivo. METHODS: The assembled device, fabricated using a photolithographic process, is composed of two layers of glass bonded together to contain a tissue chamber and a network of microchannels that allow continued tissue perfusion. RESULTS: A total of 128 tissue biopsies (from 33 patients) were maintained in microfluidic devices for an average of 72 hours. Tissue viability (measured with Annexin V and propidium iodide) was 61.1% in tissue maintained on chip compared with 68.9% for fresh tissue analysed at commencement of the experiments. Other biomarkers, including lactate dehydrogenase absorbance and trypan blue exclusion, supported the viability of the tissue maintained on chip. Histological appearances remained unchanged during the tissue maintenance period, and immunohistochemical analysis of Ki67 and caspase 3 showed no significant differences when compared with fresh tissues. A trend showed that tumours associated with poorer outcomes (recurrent tumours and Isocitrate Dehydrogenase - IDH wildtype) displayed higher viability on chip than tumours linked with improved outcomes (low-grade gliomas, IDH mutants and primary tumours). conclusions: This work has demonstrated for the first time that human glioblastoma tissue can be successfully maintained within a microfluidic device and has the potential to be developed as a new platform for studying the biology of brain tumours, with the long-term aim of replacing current preclinical GBM models and facilitating personalised treatments.

The Discovery of RNA Aptamers that Selectively Bind Glioblastoma Stem Cells

Glioblastoma (GBM) is the most aggressive primary brain tumor in adults. Despite progress in surgical and medical neuro-oncology, prognosis for GBM patients remains dismal, with a median survival of only 14–15 months. The modest benefit of conventional therapies is due to the presence of GBM stem cells (GSCs) that cause tumor relapse and chemoresistance and, therefore, that play a key role in GBM aggressiveness and recurrence. So far, strategies to identify and target GSCs have been unsuccessful. Thus, the development of an approach for GSC detection and targeting would be fundamental for improving the survival of GBM patients. Here, using the cell-systematic evolution of ligand by exponential (SELEX) methodology on human primary GSCs, we generated and characterized RNA aptamers that selectively bind GSCs versus undifferentiated GBM cells. We found that the shortened version of the aptamer 40L, which we have called A40s, costained with CD133-labeled cells in human GBM tissue, suggestive of an ability to specifically recognize GSCs in fixed human tissues. Of note, both 40L and A40s were rapidly internalized by cells, allowing for the delivery of the microRNA miR-34c and the anti-microRNA anti-miR-10b, demonstrating that these aptamers can serve as selective vehicles for therapeutics. In conclusion, the aptamers 40L and A40s can selectively target GSCs. Given the crucial role of GSCs in GBM recurrence and therapy resistance, these aptamers represent innovative drug delivery candidates with a great potential in the treatment of GBM.

Primary central nervous system tumor treatment and survival in the United States, 2004-2015

INTRODUCTION

Brain tumor treatment and survival information is generally limited in large-scale cancer datasets. We provide a clinical investigation of current patterns of care and survival estimates for central nervous system (CNS) tumors treated in the United States.

METHODS

We analyzed the National Cancer Database from 2004-2015 for all patients with diagnosis of primary CNS tumors. We describe patient demographics, treatment modality, and analyzed survival estimates.

RESULTS

512,168 patient tumor records were examined. The most common histology was meningioma (43.6%), followed by glioblastoma (22.0%), and nerve sheath tumors (10.6%). Patients had a median age of 60 years, with a female (57.9%), white (85.0%), and non-Hispanic (87.8%) predominance. Tumors were reported as World Health Organization (WHO) grade I for 55.9% of the patients, grade II for 5.9%, grade III for 4.4%, grade IV for 24.3%, and grade unknown or not applicable for 9.4%. Overall, 56% underwent surgical procedures, 30.4% received radiation, and 20.6% received chemotherapy. Radiation plus chemotherapy and surgery was the most common treatment modality in high-grade tumors (40.5% in WHO grade III and 49.3% in WHO grade IV), while surgery only or watchful waiting was preferred in low-grade tumors. Older age, male gender, non-Hispanic origin, higher number of comorbidities, and lower socioeconomic status were identified as risk factors for mortality.

CONCLUSIONS

Our analysis provides long-term survival estimates and initial treatment decisions for patients with CNS tumors in hospitals throughout the United States. Age, comorbidities, gender, ethnicity, and socioeconomic characteristics were determinants of survival.

The proton-coupled oligopeptide transporters PEPT2, PHT1 and PHT2 mediate the uptake of carnosine in glioblastoma cells

The previous studies demonstrated that carnosine (β-alanyl-L-histidine) inhibits the growth of tumor cells in vitro and in vivo. Considering carnosine for the treatment of glioblastoma, we investigated which proton-coupled oligopeptide transporters (POTs) are present in glioblastoma cells and how they contribute to the uptake of carnosine. Therefore, mRNA expression of the four known POTs (PEPT1, PEPT2, PHT1, and PHT2) was examined in three glioblastoma cell lines, ten primary tumor cell cultures, in freshly isolated tumor tissue and in healthy brain. Using high-performance liquid chromatography coupled to mass spectrometry, the uptake of carnosine was investigated in the presence of competitive inhibitors and after siRNA-mediated knockdown of POTs. Whereas PEPT1 mRNA was not detected in any sample, expression of the three other transporters was significantly increased in tumor tissue compared to healthy brain. In cell culture, PHT1 expression was comparable to expression in tumor tissue, PHT2 exhibited a slightly reduced expression, and PEPT2 expression was reduced to normal brain tissue levels. In the cell line LN405, the competitive inhibitors β-alanyl-L-alanine (inhibits all transporters) and L-histidine (inhibitor of PHT1/2) both inhibited the uptake of carnosine. SiRNA-mediated knockdown of PHT1 and PHT2 revealed a significantly reduced uptake of carnosine. Interestingly, despite its low expression at the level of mRNA, knockdown of PEPT2 also resulted in decreased uptake. In conclusion, our results demonstrate that the transporters PEPT2, PHT1, and PHT2 are responsible for the uptake of carnosine into glioblastoma cells and full function of all three transporters is required for maximum uptake.

Epidemiology and Molecular Epidemiology

Incidence, prevalence, and survival for diffuse low-grade gliomas and diffuse anaplastic gliomas (including grade II and grade III astrocytomas and oligodendrogliomas) varies by histologic type, age at diagnosis, sex, and race/ethnicity. Significant progress has been made in identifying potential risk factors for glioma, although more research is warranted. The strongest risk factors that have been identified thus far include allergies/atopic disease, ionizing radiation, and heritable genetic factors. Further analysis of large, multicenter epidemiologic studies, and well-annotated "omic" datasets, can potentially lead to further understanding of the relationship between gene and environment in the process of brain tumor development.

Egg Consumption in Relation to Glioma: A Case-Control Study

BACKGROUND AND AIMS

Data on the link between egg consumption and brain tumors are limited. The objective of this study was to investigate the association between egg consumption and odds of glioma in Iranian adults.

METHODS

In this hospital-based case-control study, 128 newly-diagnosed cases of glioma and 256 age- and sex-matched controls were enrolled from hospitals. Patients with pathologically confirmed glioma (without any other cancers) were considered eligible. We collected data on dietary intakes, including egg consumption, using a 126-item validated FFQ. Egg consumption was computed from all foods containing this food as their ingredients. Participants were categorized into tertiles of egg consumption. Conditional logistic regression was used to examine the association between egg consumption and glioma.

RESULTS

After adjustment for age, sex and energy intake, individuals in the middle tertile of egg consumption were 58% (OR 0.42; 95% CI 0.24, 0.73) less likely to have glioma compared with those in the lowest tertile. Further adjustment for other potential confounders strengthened the association; such that participants with the greatest consumption of egg intake were 62% (0.38; 0.18, 0.76) less likely to have glioma compared with those with the lowest consumption. Additional controlling for dietary intakes did not change the association significantly (0.39; 0.18, 0.85).

CONCLUSION

We found an inverse association between egg consumption at the amount of almost 2 eggs/week and odds of glioma. Further studies are required to examine this association.

Gamma knife radiosurgery for recurrent gliomas

Objective

In recent years, gamma knife radiosurgery (GKRS) has become increasingly more popular as a salvage treatment modality for patients diagnosed with recurrent gliomas. The goal of GKRS for recurrent glioma patients is to improve survival rates with minimal burden for these patients. The emphasis of this report is on local tumor control (TC), clinical outcome and survival analysis.

Methods

We performed a retrospective analysis of prospectively collected data of all patients who underwent GKRS for gliomas at the Gamma Knife Center Tilburg between 23-09-2002 and 21-05-2015. In total, 94 patients with glioma were treated with GKRS. Two patients were excluded because GKRS was used as a first stage treatment. The other 92 patients were included for analysis.

Results

TC was 37% for all tumors (TC was 50% in LGGs and 27% in HGGs). Local progression (LP) was 46% for all tumors (LP was 31% in LGGs and 58% in HGGs). New distant lesions were seen in 18% of all patients (in 5% of LGG patients and 31% of HGG patients). Median progression-free and overall survival (PFS and OS) for all patients were 10.5 and 34.4 months, respectively. Median PFS was 50.1 and 5.7 months for low and high grade tumors, respectively. Median OS was 86.6 and 12.8 months for low and high grade tumors, respectively. No serious adverse events were noted post-GKRS.

Conclusion

GKRS can safely be used as salvage treatment for recurrent glioma and seems to improve survival rates in (high grade) glioma patients with minimal burden.

Survival kinase genes present prognostic significance in glioblastoma

Cancer biomarkers with a strong predictive power for diagnosis/prognosis and a potential to be therapeutic targets have not yet been fully established. Here we employed a loss-of-function screen in glioblastoma (GBM), an infiltrative brain tumor with a dismal prognosis, and identified 20 survival kinase genes (SKGs). Survival analyses using The Cancer Genome Atlas (TCGA) datasets revealed that the expression of CDCP1, CDKL5, CSNK1E, IRAK3, LATS2, PRKAA1, STK3, TBRG4, and ULK4 stratified GBM prognosis with or without temozolomide (TMZ) treatment as a covariate. For the first time, we found that GBM patients with a high level of NEK9 and PIK3CB had a greater chance of having recurrent tumors. The expression of CDCP1, IGF2R, IRAK3, LATS2, PIK3CB, ULK4, or VRK1 in primary GBM tumors was associated with recurrence-related prognosis. Notably, the level of PIK3CB in recurrent tumors was much higher than that in newly diagnosed ones. Congruent with these results, genes in the PI3K/AKT pathway showed a significantly strong correlation with recurrence rate, further highlighting the pivotal role of PIK3CB in the disease progression. Importantly, 17 SKGs together presented a novel GBM prognostic signature. SKGs identified herein are associated with recurrence rate and present prognostic significance in GBM, thereby becoming attractive therapeutic targets.

Descriptive epidemiology of primary malignant and non-malignant central nervous tumors in Spain: Results from the Girona Cancer Registry (1994-2013)

BACKGROUND

Systematic registration of non-malignant central nervous system (CNS) tumors is a rare practice among European cancer registries. Thus, the real burden of all CNS tumors across Europe is underestimated. The Girona Cancer Registry provides here the first data on CNS tumor incidence and survival trends in Spain for all histological types, including malignant and non-malignant tumors.

METHODS

Data on all incident cases of primary CNS tumors notified to the Girona population-based cancer registry from 1994 to 2013 (n=2,131) were reviewed. Incidences rates (IRs) were standardized to the 2013 European population and annual percentage changes (EAPC) were estimated using a piecewise log linear model. 1- and 5-year observed (OS) and relative survival (RS) were also calculated. Results were expressed by sex, age-group, histological subtype and behavior.

RESULTS

The overall IR was 16.85 and increased across the period of study (EAPC=+2.2%). The proportion and IRs of malignant (50.2%; IR=9.35) and non-malignant cases (49.8%; IR=9.14) were similar; however, non-malignant tumors were more frequent in women (sex ratio=0.63). The most frequently reported histologies were meningioma (27.6%; IR=5.11) and glioblastoma (22.2%; IR=4.15), which also accounted for the highest and lowest 5-year RS (80.2%; 3.7%, respectively). Globally, 5-year RS was lower in men (42.6% vs. 58.3%, respectively) and in the elderly (64.9% for 0-14years vs. 23.0% for >74years).

CONCLUSION

This study presents a comprehensive overview of the epidemiology of malignant and non-malignant CNS primary tumors from the well-established region-wide Girona Cancer Registry (1994-2013). Incidence rates were recovered for all histologies. Survival is still dramatically associated to both age and histological subtype.

Residential radon exposure and brain cancer: an ecological study in a radon prone area (Galicia, Spain)

We aimed to know if radon concentration is associated with municipal mortality due to brain cancer in Galicia, Spain. We designed an ecological study taking as study unit Galician municipalities. To be included, municipalities had to have at least three radon measurements. We correlated radon concentrations with municipal mortality due to these malignant tumors during the period 1999-2008. We calculated the relative risk of dying of brain cancers for each municipality and correlated this value with municipal radon concentration using Spearman's Rho. 251 municipalities were included, with close to 3,500 radon measurements and an average of 14 radon measurements at each municipality. We observed a significant correlation between residential radon with brain cancer mortality for males and females and the intensity of the correlation was higher for females. These results were reinforced when the analysis was restricted to municipalities with more than 5 radon measurements: Spearman's Rho 0.286 (p-value < 0.001) and Spearman's Rho 0.509 (p-value < 0.001) for males and females, respectively. These results suggest an association between residential radon and brain cancer mortality. More research using more robust epidemiological designs is needed to confirm these findings.

Incidence and survival trends in oligodendrogliomas and anaplastic oligodendrogliomas in the United States from 2000 to 2013: a CBTRUS Report

Measuring tumor-specific trends in incidence is necessary to elucidate tumor-type contribution to overall cancer burden in the US population. Recently, there have been conflicting reports concerning the incidence of oligodendrogliomas (OD) and anaplastic oligodendrogliomas (AOD). Therefore, our goal was to examine trends in OD and AOD incidence and survival by age, gender and race. Data was analyzed from the Central Brain Tumor Registry of the United States (CBTRUS) from 2000 to 2013. Age-adjusted incidence rates per 100,000 person-years with 95% confidence intervals (CI) and annual percent changes (APCs) with 95% CI were calculated for OD and AOD by age, sex and race. Survival rates were calculated for age, sex and race using a subset of the CBTRUS data. OD and AOD incidence peaked at 36-40 and 56-60 years, respectively. AOD:OD ratio increased up to age 75. Overall, OD and AOD incidence decreased [OD: APC -3.2 (2000-2013), AOD: -6.5 (2000-2007)]. OD incidence was highest in Whites but decreased significantly (2000-2013: APC -3.1) while incidence in Black populations did not significantly decrease (2000-2013: APC -1.6). Survival rates decreased with advancing age for OD, while persons aged 0-24 had the lowest survival for AOD. The current study reports a decrease in overall OD and AOD incidence from 2000 to 2013. Furthermore, AOD makes up an increasing proportion of oligodendroglial tumors up to age 75. Lower AOD survival in 0-24 years old may indicate molecular differences in pediatric cases. Thus, surveillance of tumor-specific trends by age, race and sex can reveal clinically relevant variations.

Cancer stem cells from human glioblastoma resemble but do not mimic original tumors after in vitro passaging in serum-free media

Human gliomas harbour cancer stem cells (CSCs) that evolve along the course of the disease, forming highly heterogeneous subpopulations within the tumour mass. These cells possess self-renewal properties and appear to contribute to tumour initiation, metastasis and resistance to therapy. CSC cultures isolated from surgical samples are considered the best preclinical in vitro model for primary human gliomas. However, it is not yet well characterized to which extent their biological and functional properties change during in vitro passaging in the serum-free culture conditions. Here, we demonstrate that our CSC-enriched cultures harboured from one to several CSC clones from the human glioma sample. When xenotransplanted into mouse brain, these cells generated tumours that reproduced at least three different dissemination patterns found in original tumours. Along the passages in culture, CSCs displayed increased expression of stem cell markers, different ratios of chromosomal instability events, and a varied response to drug treatment. Our findings highlight the need for better characterization of CSC-enriched cultures in the context of their evolution in vitro, in order to uncover their full potential as preclinical models in the studies aimed at identifying molecular biomarkers and developing new therapeutic approaches of human gliomas.

The diagnostic value and functional roles of phosphoglycerate mutase 1 in glioma

Previous studies indicated that phosphoglycerate mutase 1 (PGAM1) is involved in many cancer types and promotes breast cancer progression. However, the role of PGAM1 in glioma remains unclear. The present study aimed to investigate the association of PGAM1 expression with glioma grade and the role of PGAM1 in proliferation, apoptosis, migration and invasion of glioma cells. The mRNA and protein expression of PGAM1 was analysed in glioma tissues and normal brain tissues. The expression of PGAM1 was examined further by immunohistochemical analysis. In addition, we inhibited the expression of PGAM1 in glioma cell line by siRNA to evaluate its role in glioma proliferation, apoptosis, migration and invasion. The mRNA and protein expression of PGAM1 was significantly greater in glioma than normal brain tissues. PGAM1 expression was associated with the WHO grade of glioma. siRNA knockdown of PGAM1 significantly inhibited glioma cell proliferation, promoted glioma cell apoptosis, induced S phase cell cycle arrest and inhibited glioma cell migration and invasion in vitro. PGAM1 may be associated with the grade of glioma and be involved in the biological behavior of glioma cells. PGAM1 might be a novel therapeutic target in glioma.

Conditional survival after diagnosis with malignant brain and central nervous system tumor in the United States, 1995-2012

General population-based survival statistics for primary malignant brain or other central nervous system (CNS) tumors do not provide accurate estimations of prognosis for individuals who have survived for a significant period of time. For these persons, the use of conditional survival percentages provides more accurate information to estimate potential outcomes. Using information from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program from 1995 to 2012, conditional survival percentages were calculated for 1 or 5 years of additional survival for all primary malignant brain and CNS tumors overall and by gender, race, ethnicity and age. Rates were calculated to include 1, 2, 3, 4, 5, 10 and 15 years post diagnosis. Conditional survival was also calculated in intervals from 1995-2004 to 2005-2012, to examine the potential effect that the introduction of new treatment protocols may have had on survival rates. The percentage of patients surviving one or five additional years varied by histology, age at diagnosis, gender, race and ethnicity. Younger persons (age <15 years at diagnosis) had higher conditional survival percentages for all histologies as compared to all histologies in older patients (age ≥15 years at diagnosis). The longer the amount of time post-diagnosis of a malignant brain or other CNS tumor, the higher the conditional survival. Younger persons at diagnosis had the highest conditional survival irrespective of histology. Use of conditional survival rates provides relevant additional information for patients and their families, as well as for clinicians and researchers, and helps with understanding prognosis.

Descriptive epidemiology and risk factors of primary central nervous system tumors: Current knowledge

Although comparisons are difficult due to differences in methodologies, the annual incidence rates of central nervous system (CNS) tumors range from 8.5 to 21.4/100,000 population according to cancer registries, with a predominance of neuroepithelial tumors in men and meningiomas in women. An increase in the incidence of CNS tumors has been observed during the past decades in several countries. It has been suggested that this trend could be due to aging of the population, and improvements in diagnostic imaging and healthcare access, but these factors do not explain differences in incidence by gender and histological subtypes. Several etiological hypotheses related to intrinsic (sociodemographic, anthropometric, hormonal, immunological, genetic) and exogenous (ionizing radiation, electromagnetic fields, diet, infections, pesticides, drugs) risk factors have led to analytical epidemiological studies to establish relationships with CNS tumors. The only established environmental risk factor for CNS tumors is ionizing radiation exposure. However, for other risk factors, studies have been inconsistent and inconclusive due to systematic differences in study design and difficulties in accurately measuring exposures. Thus, the etiology of CNS tumors is complex and may involve several genetic and/or environmental factors that may act differently according to histological subtype.

Shedding light on adult medulloblastoma: current management and opportunities for advances

Few evidence-based guidelines are available for the treatment of adult medulloblastoma, an extremely rare disease. Therapeutic regimens, typically modeled following pediatric protocols, consist of surgical resection followed by radiotherapy with or without adjuvant chemotherapy. Because of the rarity of this disease in adults, any treatment undertaken is based mainly on small and retrospective studies. Unlike pediatric patients, adults with medulloblastoma have been treated according to risk-adapted therapeutic strategies in only a few prospective studies. Overall, approximately 30% of patients experience recurrence and die of disease-related causes. Although the patients could respond to second-line treatments, the prognosis of patients with recurrence remains dismal. An important challenge for the future will be the biologic characterization of medulloblastoma in adults, with the identification of specific genetic patterns of patients with different prognosis and different response to targeted treatments.

Brain tumors in patients with myotonic dystrophy: a population-based study

BACKGROUND AND PURPOSE

Patients with myotonic dystrophy (DM) are at high risk of brain cancer. This study describes the spectrum of brain neoplasms in DM patients.

METHODS

Data from 1119 DM patients identified from the National Swedish Patient Register between 1987 and 2007 were linked to the National Cancer and the Cause of Death Registers. Standardized incidence ratios (SIRs) and cumulative incidence to quantify the relative and absolute risks of brain neoplasms were calculated and the Kaplan-Meier estimator was used for survival analysis. Patient follow-up started at birth or the age at the start of Swedish cancer registration (1 January 1958) and ended at the age of brain neoplasm diagnosis, death or on 31 December 2007.

RESULTS

Twenty patients developed brain neoplasm during follow-up {median age 53, range 2-76 years, accounting for a five-fold excess risk of brain tumors during the patient lifetime [SIR = 5.4, 95% confidence interval (CI) 3.4-8.1, P = 1 × 10(-5) ]}. Astrocytoma was the most common histological subtype (n = 16, 80%), and almost all cases (n = 19) developed after age 20. No statistically significant differences in gender-specific risks (SIR in men 6.3 and in women 3.8, P-heterogeneity 0.46) were observed. After accounting for competing mortality related to DM, the cumulative incidence of brain neoplasms reached 2.9% (95% CI 1.8%-4.7%) by age 70. Five-year survival after brain tumor diagnosis was 52% (95%CI 29%-75%) overall (number at risk 8) and 34% (95% CI 26%-47%) for malignant neoplasms (number at risk 5).

CONCLUSION

Despite the high relative risk of DM-related brain tumors, the absolute risk is modest. Nonetheless, careful evaluation of DM patients with new central nervous system symptoms is warranted.

Glioblastoma survival: has it improved? Evidence from population-based studies

PURPOSE OF REVIEW

Glioblastoma is the most common malignant brain tumor in adults and carries a particularly poor prognosis. Since 2005, state-of-the-art therapy consists of maximal well tolerated surgical resection followed by combined radiotherapy and chemotherapy with temozolomide. Over the past decade, further advances have been achieved in various disciplines, most prominently including antiangiogenic treatment with bevacizumab. Still, whether these therapeutic innovations have translated to the general population remains unclear.

RECENT FINDINGS

Population-based outcome and pattern of care (POC) studies have recently documented the rapid dissemination of the treatment standard to community practice across countries. This has resulted in a modest but significant increase in survival at the population level. However, the increase was significantly less marked in elderly patients in whom undertreatment is a concern. Other serious concerns address diverging POC between academic versus nonacademic centers, patients with high-income versus low-income, and racial and marital status disparities. With regard to bevacizumab treatment, there is still insufficient evidence of a beneficial impact on population-based survival, so far.

SUMMARY

Despite the rapid incorporation of the current standard treatment in clinical practice and the thereby achieved modest survival gain at the population-level, prevailing POC needs to be reconsidered and standardized, especially for elderly glioblastoma patients who bear a large disease burden and carry the worst prognosis. Future POC studies are urgently needed and would benefit from the systematic inclusion of quality-of-life data and molecular tumor markers, so that this information could be captured in population-based cancer registries.

Oncolytic adenoviruses: A thorny path to glioma cure

Glioblastoma Multiforme (GBM) is a rapidly progressing brain tumor. Despite the relatively low percentage of cancer patients with glioma diagnoses, recent statistics indicate that the number of glioma patients may have increased over the past decade. Current therapeutic options for glioma patients include tumor resection, chemotherapy, and concomitant radiation therapy with an average survival of approximately 16 months. The rapid progression of gliomas has spurred the development of novel treatment options, such as cancer gene therapy and oncolytic virotherapy. Preclinical testing of oncolytic adenoviruses using glioma models revealed both positive and negative sides of the virotherapy approach. Here we present a detailed overview of the glioma virotherapy field and discuss auxiliary therapeutic strategies with the potential for augmenting clinical efficacy of GBM virotherapy treatment.

The epidemiology of glioma in adults: a "state of the science" review

Gliomas are the most common primary intracranial tumor, representing 81% of malignant brain tumors. Although relatively rare, they cause significant mortality and morbidity. Glioblastoma, the most common glioma histology (∼45% of all gliomas), has a 5-year relative survival of ∼5%. A small portion of these tumors are caused by Mendelian disorders, including neurofibromatosis, tuberous sclerosis, and Li-Fraumeni syndrome. Genomic analyses of glioma have also produced new evidence about risk and prognosis. Recently discovered biomarkers that indicate improved survival include O⁶-methylguanine-DNA methyltransferase methylation, isocitrate dehydrogenase mutation, and a glioma cytosine-phosphate-guanine island methylator phenotype. Genome-wide association studies have identified heritable risk alleles within 7 genes that are associated with increased risk of glioma. Many risk factors have been examined as potential contributors to glioma risk. Most significantly, these include an increase in risk by exposure to ionizing radiation and a decrease in risk by history of allergies or atopic disease(s). The potential influence of occupational exposures and cellular phones has also been examined, with inconclusive results. We provide a “state of the science” review of current research into causes and risk factors for gliomas in adults.

Genomic characterization of ependymomas reveals 6q loss as the most common aberration

Ependymomas are rare tumors of the central nervous system (CNS). They are classified based on tumor histology and grade, but the prognostic value of the WHO grading system remains controversial. Treatment is mainly surgical and by radiation. An improved knowledge of ependymoma biology is important to elucidate the pathogenesis, to improve classification schemes, and to identify novel potential treatment targets. Only 113 ependymoma karyotypes with chromosome aberrations are registered in the Mitelman database. We present the first study of ependymoma genomes combining karyotyping and high resolution comparative genomic hybridization (HR-CGH). Nineteen tumor samples were collected from three pediatric and 15 adult patients treated at Oslo University Hospital between 2005 and 2012. Histological diagnoses included subependymoma and myxopapillary ependymoma (WHO grade I), ependymoma (WHO grade II) and anaplastic ependymoma (WHO grade III). Four tumors were intraspinal and 15 were intracranial. Seventeen samples were successfully karyotyped, HR-CGH analysis was undertaken on 17 samples, and 15 of 19 tumors were analyzed using both methods. Twelve tumors had karyotypic abnormalities, mostly gains or losses of whole chromosomes. Structural rearrangements were found in four tumors, in two of which 2p23 was identified as a breakpoint region. Twelve tumors displayed genomic imbalances by HR-CGH analysis with loss of material at 6q as the most common. 6q loss, which was detected by one or both methods in seven of 12 (58%) abnormal tumors, and 5p gain (observed in five tumors; 42%) were the most common genomic aberrations in this series.

Significant prevalence of antibodies reacting with simian virus 40 mimotopes in sera from patients affected by glioblastoma multiforme

BACKGROUND

Glioblastoma multiforme (GBM) is a rare tumor, which affects 1/100 000 individuals, but it represents 30% of central nervous system malignancies. GBM is a severe tumor responsible for 2% of all cancer-related deaths. Although characterized by genotypic and phenotypic heterogeneities, GBM invariably resists conventional chemo- and radiotherapies. Several chromosome alterations and gene mutations were detected in GBM. Simian virus 40 (SV40), a small DNA tumor virus, has been found in GBM specimens by some studies, while other investigations have not confirmed the association.

METHODS

An indirect enzyme-linked immunosorbent assay with 2 synthetic peptides mimicking SV40 antigens of viral capsid proteins 1-3 was employed to detect specific antibodies against SV40 in serum samples from GBM-affected patients, together with controls represented by patients affected by breast cancer and normal subjects of the same median age.

RESULTS

Our data indicate that in serum samples from GBM-affected patients (n = 44), the prevalence of antibodies against SV40 viral capsid protein antigens is statistically significantly higher (34%, P = .016 and P = .03) than in the control groups (15%), represented by healthy subjects (n = 101) and patients affected by breast cancer (n = 78), respectively.

CONCLUSION

Our data indicate that SV40, or a closely related yet undiscovered human polyomavirus, is associated with a subset of GBM and circulates in humans. Our study can be transferred to the clinical oncology application to discriminate different types of heterogeneous GBM, which in turn may address an innovative therapeutic approach to this fatal cancer.

Relative survival of patients with non-malignant central nervous system tumours: a descriptive study by the Austrian Brain Tumour Registry

BACKGROUND

Unlike malignant primary central nervous system (CNS) tumours outcome data on non-malignant CNS tumours are scarce. For patients diagnosed from 1996 to 2002 5-year relative survival of only 85.0% has been reported. We investigated this rate in a contemporary patient cohort to update information on survival.

METHODS

We followed a cohort of 3983 cases within the Austrian Brain Tumour Registry. All patients were newly diagnosed from 2005 to 2010 with a histologically confirmed non-malignant CNS tumour. Vital status, cause of death, and population life tables were obtained by 31 December 2011 to calculate relative survival.

RESULTS

Overall 5-year relative survival was 96.1% (95% CI 95.1-97.1%), being significantly lower in tumours of borderline (90.2%, 87.2-92.7%) than benign behaviour (97.4%, 96.3-98.3%). Benign tumour survival ranged from 86.8 for neurofibroma to 99.7% for Schwannoma; for borderline tumours survival rates varied from 83.2 for haemangiopericytoma to 98.4% for myxopapillary ependymoma. Cause of death was directly attributed to the CNS tumour in 39.6%, followed by other cancer (20.4%) and cardiovascular disease (15.8%).

CONCLUSION

The overall excess mortality in patients with non-malignant CNS tumours is 5.5%, indicating a significant improvement in survival over the last decade. Still, the remaining adverse impact on survival underpins the importance of systematic registration of these tumours.